1. Field of the Invention
The present invention relates to an assembly for use in a method of providing passageways in concrete structures for routing pipes, cables and conduits therethrough.
More particularly, the present invention relates a preassembled assembly comprising a plurality of duct forming sleeves or cylinders which are reinforced by a perpendicular base plate welded thereto and by a rod or rods welded across and perpendicular to the sleeves to maintain the sleeve assembly unitary and to provide means for joining the assembly to a reinforcing metal grid system or grounding system within the concrete slab.
2. Description of the Prior Art
Heretofore, various apparatus have been proposed for forming a passageway or duct in a concrete structure, such as a foundation or wall for routing pipes and/or cables therethrough. Examples of several such apparatus are disclosed in the following U.S. patents:
______________________________________ U.S. PAT. NO. PATENT ______________________________________ 2,497,058 Reid 3,205,634 Wagner 3,908,323 Stout 4,071,267 Davis 4,075,803 Alesi, Jr. 4,170,853 Kohaut ______________________________________
The U.S. Pat. No. 2,497,058 to Ried, discloses a paper tube assembly for concrete construction which forms internal cavities in the concrete structure and which includes a cylindrical paper tube fitted with end caps and supported by transverse spacer plates. The assembly is restrained against endwise movement by terminal end plates. The spacer plates and terminal end plates are provided with holes in each of the corners thereof for receipt of alignment rods therethrough.
The U.S. Pat. No. 3,205,634 to Wagner, discloses a post sleeve apparatus adapted for use in the forming of concrete foundations to faciliate the erection of structures therein by inserting posts or legs within the sleeve. The apparatus comprises a cylindrical shell, a bottom cover permanently attached to the lower opening of the shell, and a removable cover member which fits snugly into the upper opening of the shell. The removable cover is provided to prevent the flow of concrete into the tubular body.
The U.S. Pat. No. 4,170,853 to Kohaut, discloses a reuseable void forming device comprising an insert for forming a preset void in a floor, wall or other structural member. The insert comprises an elongate tubular body having a length which is less than the thickness of the structure within which it is to be encapsulated, a top cap or plate, and a bottom cap or plate. Both plates are provided with apertures or slots for passage therethrough of any desired conventional fastening means. The top cap plate is located at the upper open end of the tubular body in order to prevent the flow of concrete into the tubular body.
The U.S. Pat. No. 4,071,267 to Davis, discloses a shrouded pipe wall casting for use with split clamp couplings to provide a piping wall casting which comprises a cylindrical pipe barrel and an annular shroud having a mounting flange attached to and surrounding an open end of the pipe in order to facilitate mounting of the assembly by the flange.
The U.S. Pat. No. 3,903,323 to Stout, discloses a void creating device which is embedded in concrete structures to provide passageways within the concrete structure. The device comprises two interfitting sections, which, when fitted together, form a generally elongate hollow member of generally rectangular cross-section, closed at its opposite ends, and one or more pairs of opposed tubular projections having closure baffles at each of their ends. The baffles may be removed to enable the passage of service lines therethrough.
The U.S. Pat. No. 4,075,803 to Alesi, Jr. discloses a split duct terminator for terminating a plurality of subterranean cables. The terminator comprises a plurality of modular members each including a pair of longitudinally extending opposing walls and having at least one pair of mutually coextensive module interfacing edges which lie in a common module element interface plate that intersects the wall elements. A plurality of symmetrical, longitudinally spaced, parallel channels or pipes extend between opposing wall elements. The edges of the channel elements lie in the modular element interface plate and define a plurality of longitudinally spaced apart open channels, concave with respect to the modular element interface plate, and the longitudinal spacing between the channel elements defines symmetrical openings therebetween. The framework created by the assembled modules has passageways formed by the adjacent channels in the members which extend between the walls. The modules are used in the reconstruction of a concrete manhole.
As will be disclosed in greater detail hereinafter, the preassembled duct forming sleeve assembly of the present invention differs from those disclosed in the prior art by providing parallel metallic sleeves or cylinders which extend perpendicularly to a square or rectangular base plate and which are adapted to form passageways in concrete floors for routing of pipes or cables therethrough. Each corner of the base plate is provided with a screw bore or hole which is adapted to receive a nail or screw therethrough so that the base plate and sleeves can be mounted to the framework of a floor in order that the assembly remain in a preselected position during the process of pouring concrete into the framework. Reinforcing rod elements are also provided and are welded across and perpendicular to the sleeves to provide rigidity to the assembly and may be used to tie the assembly into the reinforcing and grounding system of the floor. Since the assembly is preassembled, and can be of varied dimensions, according to the specifications required, it is easy to install and may be installed by a forming crew rather than by electricians, as is typically the case, thus providing a cost and time effectiveness. Further, because the sleeves may be capped, the assembly has an added feature of being fire stopped to prevent the spread of fire therethrough.